3.3/3.8L ENGINE
INDEX
page page
DESCRIPTION AND OPERATION
ENGINE COMPONENTS.................. 93
ENGINE IDENTIFICATION................. 93
ENGINE LUBRICATION SYSTEM............ 93
DIAGNOSIS AND TESTING
CHECKING ENGINE OIL PRESSURE......... 96
HYDRAULIC TAPPETS.................... 94
SERVICE PROCEDURES
CRANKSHAFT END PLAY................. 99
FITTING CONNECTING ROD BEARINGS...... 97
FITTING MAIN BEARINGS................. 98
FITTING PISTONS AND RINGS............. 97
MEASURING TIMING CHAIN FOR STRETCH . . . 96
VALVE SERVICE RECONDITION........... 100
VALVE TIMING.......................... 96
REMOVAL AND INSTALLATION
CAMSHAFT BEARINGS.................. 114
CAMSHAFT........................... 113
CRANKSHAFT DAMPER................. 106
CRANKSHAFT OIL SEALÐFRONT.......... 117
CRANKSHAFT OIL SEALÐREAR........... 118
CRANKSHAFT......................... 116
CYLINDER HEAD COVER................ 107
CYLINDER HEAD....................... 108
ENGINE ASSEMBLY..................... 104
ENGINE MOUNTS...................... 102
ENGINE OIL GALLERY PLUGS............. 119OILFILTER ............................ 119
OILPAN .............................. 114
PISTON AND CONNECTING ROD.......... 115
ROCKER ARMS AND SHAFT ASSEMBLY..... 106
TAPPET REMOVAL...................... 110
TIMING CHAIN COVER................... 111
TIMING CHAIN......................... 112
VALVE STEM SEALS OR SPRINGS,
CYLINDER HEAD NOT REMOVED........ 106
VALVES AND VALVE SPRINGS............ 109
WIPER UNIT.......................... 102
DISASSEMBLY AND ASSEMBLY
HYDRAULIC TAPPETS................... 120
OIL PUMP............................ 119
CLEANING AND INSPECTION
CYLINDER HEAD....................... 120
ENGINE BLOCK AND BORE............... 121
OILPAN .............................. 121
OIL PUMP............................ 121
ADJUSTMENTS
ENGINE MOUNTS...................... 123
SPECIFICATIONS
3.3/3.8L ENGINE....................... 123
TORQUE CHART....................... 125
SPECIAL TOOLS
3.3/3.8L ENGINE....................... 127
DESCRIPTION AND OPERATION
ENGINE IDENTIFICATION
The engine identification number is located on the
rear of the cylinder block just below the cylinder
head (Fig. 1).
ENGINE LUBRICATION SYSTEM
The lubrication system is a full flow filtration pres-
sure feed type. Oil from the oil pan is pumped by a
internal gear type oil pump directly coupled to the
crankshaft. The pressure is regulated by a relief
valve located in the chain case cover. The oil is
pumped through an oil filter and feeds a main oil
galley. This oil gallery feeds oil under pressure to the
main and rod bearings, camshaft bearings. Passages
in the cylinder block feed oil to the hydraulic lifters
and rocker shaft brackets which feeds the rocker arm
pivots (Fig. 2).
ENGINE COMPONENTS
ENGINE:The 3.3L (201 Cubic Inches) and 3.8L
(231 Cubic Inches) displacement engines are 60É V
type six cylinder power plants with cast iron cylinder
blocks and aluminum cylinder heads (Fig. 3). Firing
order for these engines is 1-2-3-4-5-6. High turbu-
lence cylinder heads allow a 8.9-1 compression ratio.
CRANKSHAFT:The nodular iron crankshaft is
supported by four main bearings, with number two
being the thrust bearing. Crankshaft end sealing is
provided by front and rear rubber seals.
PISTONS:The pistons are cast aluminum alloy.
Three rings are used. Piston pins, press fitted into
place, join the pistons to forged steel connecting rods.
CAMSHAFT:The nodular iron camshaft is
mounted in four steel backed babbitt bearings. A
thrust plate located in front of the first bearing, and
bolted to the block, controls end play. Silent timing
chain drives the camshaft. This chain is enclosed by
a cast aluminum cover which also carries a front
NS3.3/3.8L ENGINE 9 - 93
aligning yokes. The yokes are secured by an align-
ment yoke retainer (Fig. 4).
PRELIMINARY STEP TO CHECKING THE
HYDRAULIC TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, read the oil pressure at the gauge.
Install a reliable gauge at pressure sending unit if
vehicle has no oil pressure gauge and check the oil
level in the oil pan. The pressure should be between
30 and 80 psi (206.8 to 551.6 kPa) at 2000 rpm.
The oil level in the pan should never be above the
MAX mark on dipstick, or below the MIN mark.
Either of these two conditions could be responsible
for noisy tappets.Oil Level Check: stop engineafter reaching normal operating temperature.
Allow 5 minutes to stabilize oil level, check dipstick.
OIL LEVEL TOO HIGH
If oil level is above the MAX mark on dip stick, it
is possible for the connecting rods to dip into the oil
while engine is running and create foam. Foam in oil
pan would be fed to the hydraulic tappets by the oil
pump causing them to become soft and allow valves
to seat noisily.
OIL LEVEL TOO LOW
Low oil level may allow pump to take in air which
when fed to the tappets, causes them to become soft
and allows valves to seat noisily. Any leaks on intake
side of pump through which air can be drawn will
create the same tappet action. Check the lubrication
system from the intake strainer to the pump cover,
including the relief valve retainer cap. When tappet
noise is due to aeration, it may be intermittent or
constant, and usually more than one tappet will be
noisy. When oil level and leaks have been corrected,
engine should be operated at fast idle to allow all of
the air inside of the tappets to be bled out.
VALVE TRAIN NOISE DIAGNOSIS
To determine source of valve train noise, operate
engine at idle with cylinder head covers removed and
listen for source of the noise.
Fig. 3 3.3/3.8L V-6 Engines
Fig. 4 Roller Tappets Aligning Yoke and Retainer
NS3.3/3.8L ENGINE 9 - 95
DIAGNOSIS AND TESTING (Continued)
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger which will
necessitate replacing the tappet, or by the plunger
partially sticking in the tappet body cylinder. A heavy
click is caused either by a tappet check valve not
seating, or by foreign particles becoming wedged
between the plunger and the tappet body causing the
plunger to stick in the down position. This heavy
click will be accompanied by excessive clearance
between the valve stem and rocker arm as valve
closes. In either case, tappet assembly should be
removed for inspection and cleaning.
CHECKING ENGINE OIL PRESSURE
Check oil pressure using gauge at oil pressure
switch location. Oil pressure should be 34.47 kPa (5
psi.) at idle or 205 to 551 kPa (30 to 80 psi.) at 3000
RPM.
(1) Remove pressure sending unit and install oil
pressure gauge (Fig. 5).
CAUTION: If oil pressure is 0 at idle, do not run
engine at 3000 RPM.
(2) Warm engine at high idle until thermostat
opens.
SERVICE PROCEDURES
VALVE TIMING
(1) Remove front cylinder head cover and all 6
spark plugs.
(2) Rotate engine until the #2 piston is at TDC of
the compression stroke.
(3) Install a degree wheel on the crankshaft pulley.
(4) With proper adaptor, install a dial indicator
into #2 spark plug hole. Using the indicator find TDC
on the compression stroke.
(5) Position the degree wheel to zero.
(6) Remove dial indicator from spark plug hole.
(7) Place a 5.08 mm (0.200 in.) spacer between the
valve stem tip of #2 intake valve and rocker arm pad.
Allow tappet to bleed down to give a solid tappet
effect.
(8) Install a dial indicator so plunger contacts the
#2 intake valve spring retainer as nearly perpendic-
ular as possible. Zero the indicator.
(9) Rotate the engine clockwise until the intake
valve has lifted .254 mm (0.010 in.).
CAUTION: Do not turn crankshaft any further
clockwise as intake valve might bottom and result
in serious damage.
(10) Degree wheel should read 6 degrees BTDC to
6 degrees ATDC.
MEASURING TIMING CHAIN FOR STRETCH
(1) Place a scale next to timing chain so that any
movement of chain may be measured.
(2) Place a torque wrench and socket on camshaft
sprocket attaching bolt and apply torque in direction
of crankshaft rotation to take up slack; 41 N´m (30 ft.
lb.) with cylinder head installed or 20 N´m (15 ft. lb.)
with cylinder heads removed.With a torque
applied to the camshaft sprocket bolt, crank-
shaft should not be permitted to move. It may
be necessary to block crankshaft to prevent
rotation.
(3) Holding a scale even, with dimension reading
as shown (Fig. 6), along edge of chain links. Apply
torque in the reverse direction to 41 N´m (30 ft. lbs.)
with cylinder heads installed, or 20 N´m (15 ft. lbs.)
with cylinder heads removed. Check amount of chain
movement.
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
(5) If chain is not satisfactory, refer to Timing
Chain Removal and Installation in this section.
Fig. 5 Checking Oil Pump Pressure
9 - 96 3.3/3.8L ENGINENS
DIAGNOSIS AND TESTING (Continued)
with an old bearing half. Do not file the rods or
bearing caps.
(1) Follow procedure specified in the Standard Ser-
vice Procedure Section for Measuring Main Bearing
Clearance and Connecting Rod Bearing Clearance
(Fig. 11).
NOTE: The rod bearing bolts should be examined
before reuse. If the threads are necked down the
bolts should be replaced (Fig. 13). Necking can be
checked by holding a scale or straight edge againstthe threads. If all the threads do not contact the
scale the bolt should be replaced.
(2) Before installing the nuts the threads should
be oiled with engine oil.
(3) Install nuts finger tight on each bolt then alter-
nately torque each nut to assemble the cap properly.
(4) Tighten the nuts to 54 N´m PLUS 1/4 turn (40
ft. lbs. PLUS 1/4 turn).
(5) Using a feeler gauge, check connecting rod side
clearance (Fig. 12). Refer to Connecting Rod Specifi-
cation Chart.
FITTING MAIN BEARINGS
CRANKSHAFT OIL CLEARANCE
Measure the journal outside diameter as shown in
(Fig. 14). Refer to Crankshaft Specification Chart.
PISTON RING SPECIFICATION CHART
Ring Position Ring Gap Wear Limit Groove Clearance Maximum Clearance
Upper Ring 0.30 - 0.55 mm
(0.012 - 0.022 in.)1.0 mm (0.039 in.) 0.030 - 0.085 mm
(0.001 - 0.003 in.)0.10 mm (0.004 in.)
Intermediate Ring 0.30 - 0.55 mm
(0.012 - 0.022 in.)1.0 mm (0.039 in.) 0.030 - 0.095 mm
(0.001 - 0.0037 in.)0.10 mm (0.004 in.)
Oil Control Ring 0.25 - 1.00 mm
(0.010 - 0.039 in.)1.88 mm (0.074 in.) 0.014 - 0.266 mm
(0.0005 - 0.009 in.)0.266 mm (0.009 in.)
Fig. 9 Check Gap on Piston Rings
Fig. 10 Measuring Piston Ring Side Clearance
Fig. 11 Checking Connecting Rod Bearing
Clearance
9 - 98 3.3/3.8L ENGINENS
SERVICE PROCEDURES (Continued)
PLASTIGAGE (OIL CLEARANCE)
MEASUREMENT
(1) Remove oil from journal and bearing shell.
(2) Install crankshaft.
(3) Cut plastigage to same length as width of the
bearing and place it in parallel with the journal axis
(Fig. 15).
(4) Install the main bearing cap carefully and
tighten the bolts to specified torque.
CAUTION: Do not rotate crankshaft or the plasti-
gage will be smeared.(5) Carefully remove the bearing cap and measure
the width of the plastigage at the widest part using
the scale on the plastigage package (Fig. 15). Refer to
Crankshaft Specification Chart for proper clearances.
If the clearance exceeds the specified limits, replace
the main bearing(s) and if necessary, have the crank-
shaft machined to next undersize.
CAUTION: Do not rotate crankshaft or the Plasti-
gage may be smeared.
CRANKSHAFT END PLAY
DIAL INDICATOR METHOD
(1) Mount a dial indicator to front of engine, locat-
ing probe on nose of crankshaft (Fig. 16).
Fig. 12 Checking Connecting Rod Side Clearance
CONNECTING ROD SPECIFICATION CHART
Connecting Rod Bearing Clearance
New Part: 0.019 - 0.073 mm
(0.0008 - 0.0029 in.)
Wear Limit: 0.074 mm
(0.003 in.)
Connecting Rod Side Clearance
New Part: 0.13 - 0.32 mm
(0.005 - 0.013 in.)
Wear Limit: 0.38 mm
(0.015 in.)
Fig. 13 Check for Stretched (Necked) Bolts
CRANKSHAFT SPECIFICATION CHART
Crankshaft End-Play
New Part: 0.09 - 0.24 mm
(0.0036 - 0.0095 in.)
Wear Limit: 0.38 mm
(0.015 in.)
Main Bearing Clearance
New Part: 0.011 - 0.059 mm
(0.0005 - 0.0024 in.)
Wear Limit: 0.076 mm
(0.003 in.)
Crankshaft Main Bearing Journal
Standard Size: 63.992 - 64.013 mm
(2.5194 - 2.5202 in.)
Crankshaft Connecting Rod Journal
Standard Size: 57.989 - 58.005 mm
(2.2831 - 2.2837 in.)
Fig. 14 Measure Crankshaft Journal O.D.
NS3.3/3.8L ENGINE 9 - 99
SERVICE PROCEDURES (Continued)
²Non±isolatedcylinder head cover to 12 N´m
(105 in. lbs.).
²Isolatedcylinder head cover to 10 N´m (90 in.
lbs.) (Fig. 32).
(4) Connect PCV hose from cylinder head cover.
(5) Install intake manifold upper plenum. Refer to
Group 11, Exhaust System and Intake Manifold for
procedure.
(6) Install Wiper Unit. Refer to Group 8K, Wind-
shield Wipers and Washers for procedure.
(7) Connect negative cable to battery.
CYLINDER HEAD
REMOVAL
(1) Drain cooling system. Refer to Group 7, Cooling
System for procedure and disconnect negative cable
from battery.
(2) Remove upper and lower intake manifolds.
Refer to Group 11, Exhaust System and Intake Man-
ifold.
WARNING: INTAKE MANIFOLD GASKET IS MADE
OF VERY THIN METAL AND MAY CAUSE PER-
SONAL INJURY, HANDLE WITH CARE.
(3) Disconnect coil wires, sending unit wire, heater
hoses and bypass hose.
(4) Remove PCV system hoses, evaporation control
system hose and cylinder head covers.
(5) Remove exhaust manifolds.
(6) Remove rocker arm and shaft assemblies.
Remove push rods andmark positions to ensure
installation in original locations.
(7) Remove the 9 head bolts from each cylinder
head and remove cylinder heads (Fig. 33).
INSTALLATION
(1) Clean all sealing surfaces of cylinder block and
cylinder heads.
(2) Install new gaskets on cylinder block (Fig. 34).
(3)The cylinder head bolts are torqued using
the torque yield method, they should be exam-
ined BEFORE reuse. If the threads are necked
down, the bolts should be replaced(Fig. 35).
(4) Necking can be checked by holding a scale or
straight edge against the threads. If all the threads
do not contact the scale the bolt should be replaced.
(5) Tighten the cylinder head bolts1-8inthe
sequence shown in (Fig. 33). Using the 4 step torque
turn method, tighten according to the following val-
ues:
²Step 1: Bolts1±8to61N´m(45ft.lbs.)
²Step 2: Bolts1±8to88N´m(65ft.lbs.)
²Step 3: Bolts1±8(again) to 88 N´m (65 ft. lbs.)
²Step 4: Bolts1±8turn an additional 1/4 Turn.
(Do not use a torque wrench for this step.)
NOTE: Bolt torque after 1/4 turn should be over 122
N´m (90 ft. lbs.). If not, replace the bolt.
(6) Tighten head bolt number 9 (Fig. 33) to 33 N´m
(25 ft. lbs.) after head bolts1±8have been tighten
to specifications.
Fig. 33 Cylinder Head Bolts Location and
Tightening Sequence
Fig. 34 Head Gasket Installation
Fig. 35 Checking Bolts for Stretching (Necking)
9 - 108 3.3/3.8L ENGINENS
REMOVAL AND INSTALLATION (Continued)
(3) Before removing valves,remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides.Identify valves to insure
installation in original location.
VALVE INSTALLATION
(1) Coat valve stems with clean engine oil and
insert them in cylinder head.
(2) Check valve tip to spring seat dimensions A
after grinding the valve seats or faces. Grind valve
tip to give 49.541 to 51.271 mm (1.950 to 2.018 in.)
over spring seat when installed in the head (Fig. 41).
Check valve tip for scoring, if necessary, the tip
chamfer should be reground to prevent seal damage
when the valve is installed.
(3) Install valve spring seat spacer on head (Fig.
42).
(4) Install new cup seals on all valve stems and
over valve guides (Fig. 41). Install valve springs and
valve retainers (Fig. 42).
(5) Compress valve springs with Valve Spring
Compressor Tool C-3422-B, with adapter 6412 install
locks and release tool.If valves and/or seats are
reground, measure the installed height of
springs dimension B, make sure measurementsare taken from top of spring seat to the bottom
surface of spring retainer. If height is greater
than 1-19/32 inches, (40.6 mm), install a 1/32
inch (.794 mm) spacer in head counterbore to
bring spring height back to normal 1-17/32 to
1-19/32 inch (39.1 to 40.6 mm).TAPPET REMOVAL
(1) Refer to Cylinder Head Removal in this section.
Cylinder Head must be removed to gain access to
tappets for service.
(2) Remove yoke retainer and aligning yokes.
(3) Use Tool C-4129 to remove tappets from their
bores. If all tappets are to be removed, identify tap-
pets to insure installation in original location.
NOTE: If the tappet or bore in cylinder block is
scored, scuffed, or shows signs of sticking, ream
the bore to next oversize and replace with oversize
tappet.
CAUTION: The plunger and tappet bodies are not
interchangeable. The plunger and valve must
always be fitted to the original body. It is advisable
to work on one tappet at a time to avoid mixing of
parts. Mixed parts are not compatible. Do not disas-
semble a tappet on a dirty work bench.
INSTALLATION
(1) Lubricate tappets.
(2) Install tappets in their original positions.
(3) With roller tappets, install aligning yokes (Fig.
43).
(4) Install yoke retainer and torque screws to 12
N´m (105 in. lbs.) (Fig. 43).
(5) Install cylinder heads. Refer to cylinder head
installation of this section for procedure.
Fig. 40 Compress Valve Springs with Special Tool
C-3422-B with Adapter 6412
Fig. 41 Checking Valve Installed Height
Fig. 42 Valve Seal and SpringÐInstallation
9 - 110 3.3/3.8L ENGINENS
REMOVAL AND INSTALLATION (Continued)
OIL PAN
(1) Clean oil pan in solvent and wipe dry with a
clean cloth. Clean all gasket material from mounting
surfaces of pan and block.
(2) Inspect oil drain plug and plug hole for
stripped or damaged threads and repair as necessary.
Install a new drain plug gasket. Tighten to 27 N´m
(20 ft. lbs.).
(3) Inspect oil pan mounting flange for bends or
distortion. Straighten flange if necessary.
(4) Clean oil screen and pipe in clean solvent.
Inspect condition of screen.
OIL PUMP
INSPECTION AND REPAIR
(1) Clean all parts thoroughly. Mating surface of
the chain case cover should be smooth. Replace pump
cover if scratched or grooved.
(2) Lay a straightedge across the pump cover sur-
face (Fig. 77). If a 0.025 mm (0.001 in.) feeler gauge
can be inserted between cover and straight edge,
cover should be replaced.
(3) Measure thickness and diameter of outer rotor.
If outer rotor thickness measures 7.64 mm (0.301 in.)
or less (Fig. 78), or if the diameter is 79.95 mm
(3.148 inches.) or less, replace outer rotor.
(4) If inner rotor measures 7.64 mm (0.301 in.) or
less replace inner rotor (Fig. 79).
(5) Slide outer rotor into chain case cover, press to
one side with fingers and measure clearance between
rotor and chain case cover (Fig. 80). If measurement
is 0.39 mm (0.015 in.) or more, replace CCC only if
outer rotor is in specification.
(6) Install inner rotor into chain case cover. If
clearance between inner and outer rotors (Fig. 81) is
0.203 mm (0.008 in.) or more, replace both rotors.
(7) Place a straightedge across the face of the
chain case cover, between bolt holes. If a feeler gaugeof 0.10 mm (0.004 in.) or more can be inserted
between rotors and the straightedge, replace pump
assembly (Fig. 82).ONLYif rotors are in specs.
(8) Inspect oil pressure relief valve plunger for
scoring and free operation in its bore. Small marks
may be removed with 400-grit wet or dry sandpaper.
(9) The relief valve spring has a free length of
approximately 49.5 mm (1.95 inches) it should test
between 19.5 and 20.5 pounds when compressed to
34 mm (1-11/32 inches). Replace spring that fails to
meet specifications (Fig. 73).
(10) If oil pressure is low and pump is within spec-
ifications, inspect for worn engine bearings or other
reasons for oil pressure loss.
ENGINE BLOCK AND BORE
CLEANING AND INSPECTION
(1) Clean cylinder block thoroughly and check all
core hole plugs for evidence of leaking.
Fig. 76 Oil Pump
Fig. 77 Checking Oil Pump Cover Flatness
Fig. 78 Measuring Outer Rotor Thickness
NS3.3/3.8L ENGINE 9 - 121
CLEANING AND INSPECTION (Continued)